But beauty isn’t the only thing these women, known as Singapore Girls, have going for them.

They train for up to 3.5 months before joining a flight crew–nearly twice the industry standard, according to Jaunted. And their education includes everything from wine-tasting classes to how to “gracefully glide-walk” through the aircraft, Jaunted says.

Singapore Girls are also subject to some strict grooming rules:

They are required to wear a distinctive sarong that’s been a hallmark of the airline since the 1970s

There are only three approved nailpolish colors

They are told which makeup is right for their complexion

And when working in First or Suites class, they must check the lavatories before and after each customer.